In 1774, he received a scholarship to follow postgraduate formation in Paris where he carried on the research of Henri-Louis Duhamel du Monceau on the growth of bones[2] catching the interest of Lazzaro Spallanzani.

Corresponding member of the French Academy of Sciences, he wrote five articles for the Diderot and d’Alembert Encyclopédie supplement.

[1] He became closely associated with many famous men of his time: Felice Fontana, Albrecht von Haller, Joseph Lieutaud, Louis-Jean-Marie Daubenton, Félix Vicq-d'Azyr, Giovanni Alessandro Brambilla...

He worked with Fontana on vipers and with Giuseppe Saverio Poli on mollusca.

[3] Troja was the inventor of the natural rubber catheter[4] and the author of several important works on the bone remodeling: the first edition was published in Paris in 1775.